1. Field of the Invention
The present invention relates to a device for introducing a tracheostomy tube into a tracheostoma with the help of an insertion aid which has a stem that can be guided through the tracheostomy tube and a conical tip that can be or is connected to the stem.
The tracheotomy is one of the oldest procedures in the history of medicine. The origins of this technique go back to antiquity. In a standard tracheotomy, artificial access to the trachea is surgically created below the larynx, typically between the 1st and 2nd or 2nd and 3rd tracheal rings. A so-called tracheostomy tube is fitted around this artificial opening to maintain respiration. Medical indications, such as e.g. the need for long-term respiration, make this technique still necessary today. As an alternative to surgery, minimally invasive puncture techniques have also been developed in recent decades. Thus in particular Ciaglia's percutaneous dilation tracheotomy, Griggs' dilation tracheotomy and Fantoni's translaryngeal tracheotomy are widely used.
2. Brief Description of the Prior Art
In Ciaglia's percutaneous dilation tracheotomy, the trachea is first punctured at a suitable point with a steel cannula. This procedure is usually carried out accompanied by bronchoscopic monitoring in order to prevent injury to the sensitive tracheal rear wall. The correct position of the cannula tip can checked by aspiration of air into a fitted-on syringe filled with liquid. If the position is correct, a teflon catheter located above the steel cannula is inserted 1 to 2 cm distally into the trachea. After the steel cannula is removed, a J-shaped guide wire (approx. 1.3 mm diameter) is advanced into the trachea through this teflon catheter. The teflon catheter can be removed afterwards. Instead, a tubular plastic catheter with a safety stop is then pushed over the guide wire for the purpose of reinforcement. One or several successive dilators can be pushed into the tracheal lumen over the reinforced guide wire with the help of a rotating movement to widen the puncture opening. Because of the conical shape of the dilators, the tissue spreads with the result that the tracheostomy tube wetted with lubricant can be inserted over the guide wire with the help of a special insertion aid (obturator). The correctness of the position is checked with the bronchoscope. The guide wire can then be removed and a balloon on the tracheostomy tube filled with air in order to seal off the trachea.
In Griggs' dilation tracheotomy, forceps are used instead of the conical dilators to spread the tissue.
In the minimally-invasive dilation technique, the laid tracheostoma is very narrow. In order to still be able to insert the tracheostomy tube, an insertion aid is used the tip of which is conically tapered similarly to the dilators. The insertion aid is a flexible rod or tube the length of which is such that it can be pushed fully through the lumen of the tracheostomy tube, with the result that the conical tip projects out of the tracheostomy tube at the distal end. In this state, the tracheostomy tube is inserted into the tracheostoma and pushed through constrictions, wherein the conical tip widens the constriction accordingly.
After the tracheostomy tube is inserted, the insertion aid must naturally be pulled out of the cannula again. This necessarily means that the diameter of the whole insertion aid, including the area of the conical tip, must be smaller than the internal diameter of the cannula. As the cannula must display a degree of stability, it also has a corresponding wall thickness of at least 0.5 to 1 mm. This in turn means that there is a stepped transition from the internal diameter to the external diameter of the cannula at the base of the conical tip of the insertion aid or, if the latter projects further over the distal end of the tracheostomy tube, at the corresponding stem section of the insertion aid. In other words, the distal end-surface of the tracheostomy tube is exposed. This in turn means that, specifically at constrictions of the tracheostoma, although the conical tip initially widens the diameter to the internal diameter of the cannula, the remaining widening must be created by the end-surface of the tracheostomy tube, which is not really designed for this. This can sometimes lead to injuries and in any event makes it much more difficult to insert the cannula.
FIG. 1 illustrates this situation with the help of the schematic representation of the distal end of a tracheostomy tube 1 from which the conical tip 8 of an insertion aid projects, wherein however the end-surface edge 9 of the tracheostomy tube 1 is exposed and makes the insertion much more difficult, in particular at constrictions of the tracheostoma.
Specifically in the case of cannulas with thick walls, this sudden transition can be a real problem. Thus, when trying to insert the cannula, the doctor often snags the cannula wall on a tracheal ring. This can result in a fracture of the cricoid cartilage.
Although the edge 9 of the tracheostomy tube 1 could also be chamfered in extension of the conical tip 8, this means that after the insertion aid, and thus also the conical tip 8, is removed a relatively sharp-edged internal edge forms the distal end of the tracheostomy tube 1 which in turn can cause injuries or wounds if it comes into contact with the sensitive trachea and thereby also cause pain which would make the long-term wearing of such a tracheostomy tube even more unpleasant for a patient.